Electro-optic display with edge seal

• US 8,610,988 B2
• Filed: 03/06/2007
• Issued: 12/17/2013
• Est. Priority Date: 03/09/2006
• Status: Active Grant

• Current Assignee: E Ink Holdings Incorporated, FlexEnable Limited (Plastic Logic JSC)
• Original Assignee: E Ink Holdings Incorporated
• Inventors: Zehner, Robert W., Burns, Seamus Ewan
• Primary Examiner(s): SAHLE, MAHIDERE S
• Application Number:
  US11/682,348
• Publication Number:
  US 20070211002A1
• Time in Patent Office: 2,478 Days
• Field of Search: 359295-298, 359/245, 359/265, 359/290, 359/291, 345/84, 345/105, 345/107
• US Class Current: 359/245
• CPC Class Codes: G02F 1/1334 based on polymer dispersed liquid crystals, e.g. microencapsulated liquid crystals
• CPC Class Codes: G02F 1/1339 Gaskets; Spacers; Sealing of cells
• CPC Class Codes: G02F 1/1341 Filling or closing of cells
• CPC Class Codes: G02F 1/1391 Bistable or multi-stable liquid crystal cells G02F1/141 takes precedence
• CPC Class Codes: G02F 1/141 using ferroelectric liquid crystals
• CPC Class Codes: G02F 1/167 by electrophoresis
• CPC Class Codes: G02F 1/16755 Substrates
• CPC Class Codes: G02F 1/1679 Gaskets; Spacers; Sealing of cells; Filling or closing of cells

Abstract

An electro-optic display (100) comprises a backplane (102); an electro-optic layer (112) adjacent the backplane (102), the electro-optic layer (112) being smaller than the backplane (102) so as to leave a peripheral portion of the backplane extending beyond the edges of the electro-optic layer (112); and a protective layer (118) disposed on the opposed side of the electro-optic layer (112) from the backplane (102), a peripheral portion of the protective layer (118) extending beyond the edges of the electro-optic layer and being adhered (at 120) to the backplane (102).

Claims

1. An electro-optic display comprising:

a backplane;

a layer of electro-optic material disposed adjacent the backplane, the layer of electro-optic material being smaller in both dimensions than the backplane so as to leave a peripheral portion of the backplane extending beyond the edges of the layer of electro-optic material; and

a protective layer disposed on the opposed side of the layer of electro-optic material from the backplane, a peripheral portion of the protective layer extending beyond the edges of the layer of electro-optic material, being disposed closer to the backplane than the portion of the protective layer covering the layer of electro-optic material, and being adhesively secured to the peripheral portion of the backplane.

2. An electro-optic display according to claim 1 wherein both the backplane and the protective layer are formed of flexible polymeric films.

3. An electro-optic display according to claim 2 wherein the backplane comprises organic transistors printed on a polymeric film.

4. An electro-optic display according to claim 1 wherein the backplane comprises a barrier coating adjacent the layer of electro-optic material, the barrier coating having a water vapor transmission rate not exceeding about 0.05 g/m²/day at 40°

C.

5. An electro-optic display according to claim 1 wherein the adhesive used to secure the protective layer to the backplane has a water vapor transmission rate not exceeding about 50 g/m²/day at 40°

C.

6. An electro-optic display according to claim 1 wherein the adhesive used to secure the protective layer to the backplane has a thickness not greater than about 25 μ

m and a width, parallel to the plane of the backplane, of at least about 1 mm.

7. An electro-optic display according to claim 1 further comprising a light-transmissive front electrode disposed on the opposed side of the layer of electro-optic material from the backplane, and a front substrate disposed on the opposed side of the front electrode from the layer of electro-optic material, the front substrate mechanically supporting the front electrode, and wherein the protective layer is adhesively secured to the front substrate.

8. An electro-optic display according to claim 1 wherein the electro-optic material comprises a rotating bichromal member or electrochromic material.

9. An electro-optic display according to claim 1 wherein the electro-optic material comprises an electrophoretic material comprising a plurality of electrically charged particles disposed in a fluid and capable of moving through the fluid under the influence of an electric field.

10. An electro-optic display according to claim 9 wherein the electrically charged particles and the fluid are confined within a plurality of capsules or micro cells.

11. An electro-optic display according to claim 9 wherein the electrically charged particles and the fluid are present as a plurality of discrete droplets surrounded by a continuous phase comprising a polymeric material.

12. An electro-optic display according to claim 9 wherein the fluid is gaseous.

13. An electronic book reader, portable computer, tablet computer, cellular telephone, smart card, sign, watch, shelf label or flash drive comprising a display according to claim 1.

14. A process for sealing an electro-optic display, the process comprising:

providing a layer of electro-optic material;

disposing a backplane adjacent the layer of electro-optic material, the backplane being larger than the layer of electro-optic material so as to leave a peripheral portion of the backplane extending beyond the edges of the layer of electro-optic material;

disposing a protective layer adjacent the layer of electro-optic material on the opposed side thereof from the backplane, the protective layer being larger than the layer of electro-optic material so as to leave a peripheral portion of the protective layer extending beyond the edges of the layer of electro-optic material;

disposing the peripheral portion of the protective layer closer to the backplane than the portion of the protective layer covering the layer of electro-optic material; and

adhesively securing the peripheral portion of the protective layer to the peripheral portion of the backplane, thereby sealing the display.

15. A process according to claim 14 wherein both the backplane and the protective layer are formed of flexible polymeric films.

16. A process according to claim 14 wherein the backplane comprises a barrier coating adjacent the layer of electro-optic material, the barrier coating having a water vapor transmission rate not exceeding about 0.05 g/m²/day at 40°

C.

17. A process according to claim 14 wherein the adhesive used to secure the protective layer to the backplane has a water vapor transmission rate not exceeding about 50 g/m²/day at 40°

C.

18. A process according to claim 14 further comprising providing a light-transmissive front electrode disposed on the opposed side of the layer of electro-optic material from the backplane, and a front substrate disposed on the opposed side of the front electrode from the layer of electro-optic material, the front substrate mechanically supporting the front electrode, and adhesively securing the protective layer to the front substrate.

19. A process according to claim 14 wherein the electro-optic material comprises a rotating bichromal member or electrochromic material.

20. A process according to claim 14 wherein the electro-optic material comprises an electrophoretic material comprising a plurality of electrically charged particles disposed in a fluid and capable of moving through the fluid under the influence of an electric field.

21. A process according to claim 20 wherein the electrically charged particles and the fluid are confined within a plurality of capsules or microcells.

22. A process according to claim 20 wherein the electrically charged particles and the fluid are present as a plurality of discrete droplets surrounded by a continuous phase comprising a polymeric material.

23. A process according to claim 20 wherein the fluid is gaseous.